Electric space heater



March 7, 1967 L. o. HARMON ELECTRIC SPACE HEATER 2 Sheets-Sheet 1 FiledDec. 22, 1964 Lo u/s O.HARMO N NVENTOR gnaw March 7, 1967 1.. o. HARMON3,308,272

ELECTRIC SPACE HEATER Filed Dec. 22. 1964 2 Sheets-Sheet 2 Q Lou /5 QHARM 01v INVENTOR ATTORNEY United States Patent 3,308,272 ELECTRIC SPACEHEATER Louis 0. Harmon, RD. 5, Amsterdam, N.Y. 12010 Filed Dec. 22,1964, Ser. No. 420,374 2 Claims. (Cl. 219-530) This invention relates toa novel electric space heater wherein the electric resistance element isenclosed in a radiator tube for heating a small amount of air confinedin the tube and which in turn heats the radiator tube by conduction.

Another object of the invention is to provide an electric space heaterwherein the radiator tube heats fins which surround and are disposedtransversely of the tube by direct radiation, and which fins in turnheat the ambient air disposed between and around said fins for providingthe maximum amount of heat to the atmosphere surrounding the heater fromthe electricity utilized.

A further and primary object of the present invention is to provide anovel means of supporting a coiled electric resistance element in theradiator tube to enable the use of a resistance element which is notcovered with electrical insulating material, so that the heat producedthereby may be utilized to a maximum extent.

Various other objects and advantages of the invention will hereinafterbecome more fully apparent from the following description of thedrawings, illustrating a presently preferred embodiment thereof, andwherein:

FIGURE 1 is a plan view of the electric space heater;

FIGURE 2 is an enlarged fragmentary longitudinal sectional view thereof,taken substantially along a plane as indicated by the line 22 of FIGURE1;

FIGURE 3 is a cross sectional view of the heater taken substantiallyalong a plane as indicated by the line 3-3 of FIGURE 2;

FIGURE 4 is a side elevational view, partially diagrammatic, showing aportion of the heater;

FIGURE 5 is a cross sectional view of a part of the heater, takensubstantially along a plane as indicated by the line 5-5 of FIGURE 2;and

FIGURE 6 is a fragmentary bottom plan view of a part of the heater, on areduced scale relative to FIG- URE 2.

Referring more specifically to the drawings, the electric space heaterin its entirety is designated generally 8 and includes an elongatedradiator tube 9 which is preferab ly formed of copper. As best seen inFIGURE 2, a thin metal sleeve 10 is disposed on and closely embraces thetube 9, and provides a support for a plurality of heat radiating platesor fins 11, each of which radiates in all directions from the sleeve 10.The fins 11 are formed of thin sheet metal and are disposed crosswise ofthe axis of the tube 9 and the sleeve 10 and in spaced apart relation toone another.

A rod 12 is disposed in the tube 9 and rests on a bottom portionthereof. The rod 12 is of approximately the same length as the tube 9and supports a plurality of U-shaped spring metal clips 13, each havingan intermediate portion 14, as seen in FIGURE 3, which is welded orotherwise secured, as seen at 15, to an upper surface of the rod 12.Thus the spring clips 13 extend upwardly from the rod 12 and aredisposed substantially perpendicular thereto. Each spring clip 13 hasout-turned terminals 16 defining the upper ends of the legs thereof. Acollar 17 of electrical insulating material is detachably supported ineach spring clip 13. Each collar 17 has an annular groove 18 formed inthe periphery thereof in which the spring clip 13 engages, as seen inFIGURES 2, 3 and 4. Thus, the rod 12 and spring clips 13 provide asupport for supporting a plurality of the insulators 17 in predeterminedspaced apart relation to one another, and said'rod'12, the

3,308,272 latented Mar. 7, 1967 spring clips 13 and the insulators 17combine to form a support for the coiled wire 19.

- The ends of the tube 9 extend beyond the ends of the sleeve 10 forreceiving corresponding electrical insulating members 20, each of whichis elongated and has a recess opening through an inner end 21 thereof,and which recess includes an outer portion 22 opening through said end21 and an inner portion 23 which is smaller in diameter than the outerportion. Each insulator 20 has a shallow recess 24 which opens throughits outer end face 25 and which combines with the recess portion 23 toform a transverse wall 26 having a central opening 27.

A screw 28 extends outwardly through the opening 27 of each insulator20. A nut 29 is mounted on each screw 28, adjacent the head 30 of saidscrew, and said nut and the screw head are disposed in the recessportion 23. The two terminals 31 of the coiled resistance element 19 areclamped between the screw heads 30 and the nuts 29 and thereby aresecured to the screws 28, and a nut 32 is threaded on each screw 28 andis disposed in the recess 24 and bears against the wall 26 of theinsulator 20, in which said screw is mounted, for securing the screws tothe insulators 20 and for thus securing the ends of the resistanceelement 19 to said insulators.

One of the terminals 31 is first thus attached to one of the insulators20, after which said insulator is applied to one end of the tube 9 bysaid tube end being received in the recessed portion 22 of saidinsulator which is of a proper size and shape to receive the tube end.The end of the tube will abut an annular shoulder 33 formed at the innerend of the recessed portion 22, so that the inner end face 21 of theinsulator 20 will be spaced slightly from the adjacent end of the sleeve10. The resistance element 19 is sufficiently resilient so that theother end thereof, which will protrude from the other end of the tube 9,can be readily fastened to the screw 28 of the other insulator 20, asheretofore described, after which said screw can be clamped to theinsulator by the nut 32, and the last mentioned insulator 20 then isapplied to the other end of the tube 9.

A setscrew 44 threadedly engages a radial bore 45 of each insulator 20,which bores open into the recess portions 22, so that the setscrews 44can be tightened for clamping the insulators 20 to the ends of the tube9. The aforedescribed connection of the ends 31 of the resistanceelement 19 to the insulators 20 holds the resistance element under aslight tension to prevent sagging of the resistance element between theinsulator collars 17 to retain the resistance element out of contactwith the tube 9.

- The screws 28 additionally function as electrical terminals for theends of the resistance element 19. Two insulation covered conductorwires 34 have bare terminal ends 35 which engage around the screws 28beyond the nuts 32, as seen in FIGURE 5. A cap 36 of electricalinsulating material is detachably mounted beyond the outer end of eachinsulator 20. Each cap 36 has an internally threaded sleeve 37 imbeddedtherein which opens into a recessed inner face 38 thereof. The sleeves37 are threaded on the remote ends of the screws 28 for clamping theterminals 35 thereon between said sleeves 37 and the nuts 32. Theconductor wires 34 are thus electrically connected to the two ends 31 ofthe resistance element 19. Each insulator 20 has a recess 39 openinginto its recess 24 and outwardly of a part of the periphery thereof, andeach cap 36 has a recess 40 opening into its recess 38 and outwardly ofits periphery and which recesses 39 and 40 register with one another toform passages, when the caps 36 are applied to the insulators 20,through which portions of the insulation covered conductor wires 34extend.

The other ends of the conductors 34 are electrically connected byconventional electrical connectors 41 to complementary ends of twoelectrical conductor wires 42, the other ends of which are connected ina conventional manner to an electric plug 43 which may be connected toany conventional electrical outlet for providing an elec tric circuitincluding the resistance element 19.

It will be readily apparent that when an electric current passes throughthe resistance element 19, said element will be heated to heat the airconfined in the tube 9 by which the heat will be conducted to said tube.The sleeve 10 and fins 11 will be heated by the heat radiating from thetube 9 to heat the air in the spaces between fins 11 and around saidfins. It will thus be apparent that the heat produced by the electriccurrent employed will be utilized to a maximum extent for heating theambient air around and adjacent the heater 8.

Insulators 20, caps 36, and the insulators 17 are all preferably formedof a refractory material.

The space heater 8 obviously may be made in various lengths and crosssectional sizes, and various other modifications and changes arecontemplated and may obviously be resorted to, without departing fromthe function or scope of the invention, as hereinafter defined by theappended claims.

I claim as my invention:

1. An electric space heater comprising an elongated metal heat radiatingtube, a plurality of heat conducting fins supported on and extendingtransversely in all directions from said tube and disposed in spacedapart relation to one another, a coiled electrical resistance elementextending longitudinally through said tube, terminals connected to theends of said resistance element and adapted to electrically connect saidresistance element to two electrical conductors; electrical insulatorsdetachably connected to and extending outwardly from the ends of saidtube and supporting said terminals beyond the tube ends for holding theresistance element extended, supporting means detachably mounted in saidtube and supporting said resistance element electrically insulated fromthe tube between said terminals, said supporting means comprising anelongated rod disposed in and resting on a part of said tube, aplurality of collars of electrical insulating material through whichsaid resistance element extends, a plurality of spring clips fixed toand projecting transversely from said rod and embracing said collars forsupporting said collars in spaced apart substantially aligned relationto one another, each of said insulators including an elongated body ofelectrical insulating material having a recess opening through an innerend thereof for receiving one of said tube ends, a restricted cavitydisposed beyond and communicating with said recess for accommodating apart of said terminal to which one of said ends of the resistanceelement is secured, a transverse wall defining an outer end of saidcavity having an opening through which a part of the terminal extends,and a fastening of electrical conducting material secured to a part ofsaid terminaland bearing against an outer side of said transverse wallfor securing the terminal to the insulator.

2. An electric space heater as in claim 1, said insulator having anouter end face provided with a recess in which said fastening isreceived; a cap of electrical insulating material having a sleeve ofelectrical conducting material imbedded in said cap and opening throughan inner end thereof for threadedly engaging an outer end of theterminal for clamping an exposed end of one of said electricalconductors to the terminal between said fastening and sleeve and forenclosing said electrical conductor end between said insulator and cap.

References Cited by the Examiner UNITED STATES PATENTS 1,997,146 4/1935Hynes 219-534 2,058,769 10/1936 Brown 338274 X 2,372,150 3/1945Whittaker 338236 2,478,808 8/1949 Deal 338-3l7 X 2,562,940 8/1951 Packer33 8'236 2,995,646 8/1961 Kawalle 338274 X ANTHONY BARTIS, PrimaryExdminer.

1. AN ELECTRIC SPACE HEATER COMPRISING AN ELONGATED METAL HEAT RADIATINGTUBE, A PLURALITY OF HEAT CONDUCTING FINS SUPPORTED ON AND EXTENDINGTRANSVERSELY IN ALL DIRECTIONS FROM SAID TUBE AND DISPOSED IN SPACEDAPART RELATION TO ONE ANOTHER, A COILED ELECTRICAL RESISTANCE ELEMENTEXTENDING LONGITUDINALLY THROUGH SAID TUBE, TERMINALS CONNECTED TO THEENDS OF SAID RESISTANCE ELEMENT AND ADAPTED TO ELECTRICALLY CONNECT SAIDRESISTANCE ELEMENT TO TWO ELECTRICAL CONDUCTORS; ELECTRICAL INSULATORSDETACHABLY CONNECTED TO AND EXTENDING OUTWARDLY FROM THE ENDS OF SAIDTUBE AND SUPPORTING SAID TERMINALS BEYOND THE TUBE ENDS FOR HOLDING THERESISTANCE ELEMENT EXTENDED, SUPPORTING MEANS DETACHABLY MOUNTED IN SAIDTUBE AND SUPPORTING SAID RESISTANCE ELEMENT ELECTRICALLY INSULATED FROMTHE TUBE BETWEEN SAID TERMINALS, SAID SUPPORTING MEANS COMPRISING ANELONGATED ROD DISPOSED IN AND RESTING ON A PART OF SAID TUBE, APLURALITY OF COLLARS OF ELECTRICAL INSULATING MATERIAL THROUGH WHICHSAID RESISTANCE ELEMENT EXTENDS, A PLURALITY OF SPRING CLIPS FIXED TOAND PROJECTING TRANSVERSELY FROM SAID ROD AND EMBRACING SAID COLLARS FORSUPPORTING SAID COLLARS IN SPACED APART SUBSTANTIALLY ALIGNED RELATIONTO ONE ANOTHER, EACH OF SAID INSULATORS INCLUDING AN ELONGATED BODY OFELECTRICAL INSULATING MATERIAL HAVING A RECESS OPENING THROUGH AN INNEREND THEREOF FOR RECEIVING ONE OF SAID TUBE ENDS, A RESTRICTED CAVITYDISPOSED BEYOND AND COMMUNICATING WITH SAID RECESS FOR ACCOMMODATING APART OF SAID TERMINAL TO WHICH ONE OF SAID ENDS OF THE RESISTANCEELEMENT IS SECURED, A TRANSVERSE WALL DEFINING AN OUTER END OF SAIDCAVITY HAVING AN OPENING THROUGH WHICH A PART OF THE TERMINAL EXTENDS,AND A FASTENING OF ELECTRICAL CONDUCTING MATERIAL SECURED TO A PART OFSAID TERMINAL AND BEARING AGAINST AN OUTER SIDE OF SAID TRANSVERSE WALLFOR SECURING THE TERMINAL TO THE INSULATOR.